Among the many representations of cross-species suckling in medieval French literature, two fourteenth-century examples are remarkable for their portrayals of fantastic creatures that nurse human infants. In Le conte du papegau (The Tale of the Parrot), a unicorn suckles a motherless child, and in Tristan de Nanteuil (Tristan of Nanteuil), a siren nurses a child abandoned at sea. The substitution of a fantastic creature for the wild animal that more commonly suckles an abandoned child emphasizes the fictionality of the episode. This emphasis on the fictional and the fantastic opens a moment of reflection in which the relationships defined through suckling come under consideration. Fantasy disrupts the conventional representation of kinship bonds based on blood and introduces symbolic relationships based on shared milk; cross-species nursing defines cross-species kinships.